Reversible mantle for gyratory crushers



J. E. KENNEDY 7 2,467,938

REVERSIBLE MANTLE FOR GYRATORY CRUSHERS April 19, 1949.

2 Sheets-Sheet 1 Filed Dec. 15, 1945 V! y R0 f A E 7 W M aw 0 J pATTORNEYS 'April 19, 1949. J. E. KENNEDY 2,467,938

REVERSIBLE MANTLE FOR GYRATORY (FRUSHERS 2 Sheets-Sheet 2 Filed Dec. 15,1945 I gyw 6 INVENTQR JOSEPH E. KENNEDY BY 1 WM ATTORNEYS Patented Apr.19, 1949 UNITED STATES PATENT OFFICE REVERSIBLE MANTLE FOR GYRATORYCRUSHERS 9 Claims.

other materials, is that as the mantle and grinding ring wear away, thespace between these two elements gradually becomes greater, and the fineness of the crushed stone or ore gradually becomes larger, althoughcertain arrangements are provided for adjusting the vertical position ofthe mantle as the wearing progresses. However, at some stage of theoperation, the mantle and grinding ring must be replaced, and in orderto do this, the upper portion of the crusher must be taken apart toremove the old grinding ring and to permit the removal of the worn mantlfrom the main shaft of the crusher. The mantle and grinding ring ofcrushers of this type are made of expensive alloy steel such as castmanganese steel, and therefore, the cost of replacing these elements isconsiderable.

The primary object, therefore, of the present invention is to provide animproved mantle and grinding ring combination which will have a greaterlength of life and which will therefore reduce the number of exchangesto be made.

A further object of the invention is to provide an improved grindingring which is reversible, one end of which has a special constructionwhich cooperates in an important manner with the mantle when partiallyworn.

According to the features of my invention, the improved mantle andgrinding ring combination includes a mantle having a lower crushingsection of unusual thickness and which, according to a preferredconstruction, includes two special inclined angles of nip on its outerperiphery, a grinding ring having a lower conical-shaped surface mountedopposite the lower portion of the mantle, a substantially verticalsurface mounted opposite the central portion of the mantle, and afunnel-shaped surface extending from said upright vertical surface tothe top of the ring, the thickness of the ring at the top beingsubstantially greater than at the bottom, whereby the ring may bereversed when the lower portion of the mantle and ring have been wornaway, so that the extra thickness in the reversed grinding ring offsetsthe worn-away portion of the mantle and 2 substantially doubles the lifeof the crushing elements.

A preferred mantle construction according to my invention comprises amantle of generally conical form but in which the outside surfaceincludes various angles of nip, such as four in one form, the lowersurface having a relatively steep angle, the next surface being somewhatless steep, and the third surface having approximately the steepness ofthe first, while the fourth surface is somewhat steeper than the first.

The grinding ring, according to a preferred form, is a one-piece castring, but it may be made up of a plurality of concaves assembled in asuitable backing.

My improved apparatus will be described more in detail hereinafter inconnection with the accompanying drawings, in which:

Figs. 1 and 2 are broken vertical views partly in section showing thedetails of construction of the improved crushing elements, Fig. 2showing a modified form of ring.

Fig. 3 is a quarter plan view looking down on the grinding ring andmantle of Fig. 2.

Referring to Fig. l, the crusher comprises a lower shel1 In of annularconstruction and which may be a heavy casting, the shell including aheavy flange l2 and a tapered annular surface l3 extending from ashoulder M. A split top shell l-6 having upper and lower annular taperedsurfaces lfl, rests on the surface IS. The shell [6 is provided withsuitable shoulders as shown which support outwardly extending upper andlower flanges of a grinding ring 20 mounted therein. The ring 20 ispreferably a solid one-piece ring of cast manganese steel and is held inposition against rotation in the shell It by means of two or more dowelpins 22 which may be at the juncture of the sections of the shell H5 or90 therefrom. When the ring 20 and shell it are assembled, the twohalves of the shell l6 are bolted together by means of bolts 24. The topof the crusher includes a spider 26 having a lower flange and shoulderconstruction similar to that of the upper portion of the shell If], soas to fit the shell l6, this construction including the tapered annularsurface 13 to fit the matching tapered surface ill of the shell IS. Theflange of the spider is clamped to the flange of the shell [0 by meansof bolts 28. When these bolts are drawn up tight with the taperedsurfaces l3 engaging the matching surfaces [8, ring 20 is held in arigid position which makes a solid anvil against which the stone or oreis broken in the crushing operation.

The spider 26 includes two arms 30 and a bearing head 32 for supportinga main shaft 34 in any suitable manner, not shown, but which may besomewhat like that shown in the above-mentioned patent.

The shaft 34 extends substantially axially downwardly through thecrusher into a housing 38 in which a mechanism is mounted for gyratingthe lower end of the shaft. The portion of the shaft 34 opposite thegrinding ring is of generally frusto-conical form and adapted to receivea mantle core 40 which fits over the frusto-conical section of theshaft. A mantle 42 is mounted directly over the frusto-conical outersurface of the mantle core 40, and extends slightly below the ring 20.The upper part of the core and mantle are covered with a lock nut sleeve44, a clamp collar 46 and a lock nut sealing ring 48.

The stone to be crushed is fed into the crusher through the spacesbetween the arms 30,'and the crushed material falling off the mantle d2slides the crushed material and dust by means of a. conical-shaped capseal 55 to which is attached a rubber hood the upper portion of which isattached to the main shaft 34 under the mantle core 40.

In accordance with a preferred form of my invention, I make the lowerportion of the mantle i2 extra thick and of a particular shape. As shownin the drawing, this portion of the mantle t2 differs distinctly fromthe standard mantle by including an integral bulbous section at thelower portion of the mantle. The extra thickness may be represented asoutside of the dotted line. This particular section of the mantle asillustrated has nip surfaces 62 and M, while the upper portion of themantle has differently sloping nip surfaces 56 and 68.

A preferred form of grinding ring 20, as constructed and illustrated inFig. 1, includes a lower section having a frusto-conical nip surface I!)of standard construction, which is mounted opposite the surfaces .62 and64. The central section of the grinding ring 20. includes asubstantially vertical or cylindrical surface 1-2 while the upperportion of the grinding ring has a funnel-shaped grinding surface 14which is at. a different angle to the surface 12 than that of thesurface iii, such that the upper part of the element 2% is substantiallythicker than the lower portion. In other words, the surface 14 is at agreater distance from the symmetrical shell it than is the surface 70.The ring 20, as shown, has three bearing surfaces on the shell [5,, anupper bearing surface, a central bearing surface and a lower bearingsurface, but may bear against the shell IS its entire height.

As an example illustrative of a combination grinding ring and mantleconstructed in accordance with the present invention shown in Fig. l.and for a particular size, the top opening between the mantle andconcave may be approximately four and three-quarter inches. The surfaces62 and 6 3 are at angles of about 2 and 16, respectively, with respectto the surface It. The surface 66 is at an angle of about 265 withrespect to the vertical surface 12, while the angle between the surfaces88 and M is about 22. The mantle. is about two and seven-sixteenthinches thick at its lower end and over 2.5 inches where the surfaces 62and 64 join. It will be understood that these angles will Vary somewhatas the lower end of the main shaft 34 is gyrated to move successiveareas of the perimeter of the mantle toward the grinding ring to crushthe rock or other material around its outside surface. In Fig. 1 themantle 42 is shown with its lower portion moved to the left. Thecrusher, as shown, is adapted to grind the material to a size ofapproximately onesixteenth of an inch.

In the example, as illustrated in Fig. 1, the grinding ring for use withthe mantle described above may have any suitable thickness. As anexample, the thickness bearing against the lower part of shell It may beabout one and one-half inches, while the upper thickness bearing againstthe shell I6 is two inches.

The. construction shown in Fig. 2 of the drawings is in. general thesame as that shown in Fig. 1, except for a difference in the grindingring structurev and in the shape of the inner surface of the top shell.In Fig. 2 a top shell Ilia has substantially the upper and lower bearingsurfaces as the shell it in Fig. 1', but has a more or less regular ovalinside central section which bears directly against a. grinding ring 20amade up of a plurality of concaves .16, 16a and 16b mounted in a backcasting of zinc 18-. It will be noted in Fig. 2 that the zinc backingwhich holds the concaves 16, 16a and 15b in place fits exactly theinside surface of the shell I600. The grinding ring 20a is reversiblethe same as the ring, 20 described above, and the concaves 16, 18a and167) are made thicker on the top than on the bottom so that after thelower portions of the concaves of the ring have been worn away alongwith the lower portion of the mantle, the. ring 20a may be reversed andthe extra thickness be taken advantage of in the manner described abovein connection with Fig. 1. The concaves L5, 16a and 16b are preferablymade of the same material as that of the grinding ring 20.

Fig. 3 shows a top view of the grinding ring: 2011 in its relation tothe mantle 42, the mantle being shown as removed from the mantle core orwithout the core til, shaft 34' and elements i l,v 46 and 48. In Fig. 3,it will be noted that the concaves I6. 160. and 7617 are not identical,but that the center concave 16a in the quarter showing, is a key concavemounted between concaves H5 and 16b. It will be noted furthermore thatin this figure the zinc backing 18 extends between the individualconcaves and that the'mounting; of. the concaves in the zinc provides asolidgrinding ring, which in use is backed up by the: shell Mia. Theconcaves are of such a size and shape. with respect to the positionsthey occupy in the ring that the interveningzinc exposed on the innersurface of the ring is comprised of relatively narrow strips which areusuallynot more than onequarter inch wide.

The top of the mantle as shown in Fig. 3 is provided with pockets 8llforreceiving keysonthe sealing ring; 48 for keying the mantle to the core40, the upper portion of the latter having pockets, not shown, oppositeto thepockets 80, as will be understood- The grinding ring 20a as shownin Figs. 2 and- 3 has the same surfaces 70, 12 and 14, and in the samerelationship to eachother as those of the grinding ring 20 of Fig. 1. Ineach case instead of having surface Has a regular cylindrical surface,it may be rounded so as to blend smoothly into the surfaces 10- and 1-4.

In the use of the apparatus as described and illustrated above. thelower portionof the mantle. and grinding ring wear away relativelyraster.

than the central and upper portions, and therefore when the mantle hasbeen worn away down to approximately the dotted line, the lower portionof the grinding ring will have become thinner to such an extent that itwould normally need to be replaced. However, instead of taking the Wholeapparatus to pieces, and putting on a new mantle and ring, the grindingring is simply reversed so that the thicker upper end, as shown in thedrawings, is mounted opposite the worn away lower section of the mantle42. The extra thickness in the reversed grinding ring will compensatefor the worn away lower portions of the ring and mantle, and therebyproduce a combination in which the spacing between the mantle and ringis approximately that of the original spacing. With the ring reversed,the crusher now has a long period of use before the thicker section ofthe ring is worn down and before the mantle is worn sufficiently torequire replacing.

If desired, the grinding ring and mantle 42 may be made in two or moresections similar to that of the shell 16. The grinding ring and mantlemay be made in various sizes and each may be provided with differentangles of nip from those shown and described in connection with thedrawings. Other changes may be made in the construction and arrangementwithout departing from the spirit and scope of the invention as definedby the claims.

What I claim as new is:

1. In a crusher of the gyratory type in which a mantle of generallyfrusto-conical form is moved in succession toward and away from portionsof a surrounding grinding ring the improve- I ment which comprises, amantle the lower portion of which includes a substantial thickness ofmetal over and above that of the standard mantle, and a grinding ringreversible end for end having a lower portion of standard thickness andan upper portion which is substantially thicker than the lower portion,whereby the ring may be reversed after the lower portions of the ringand mantle have been worn away substantially to thereby increase theeffective life of the grinding ring and mantle and provide a structurewhen the ring is reversed in which the greater thickness of the upperportion of the ring replaces the worn lower portion of the mantle.

2. A crusher as defined by claim 1 in which the lower portion of saidmantle opposite the lower portion of the grinding ring includes anupwardly inclined outer frusto-conical surface of substantially steeperslope than the general slope of the mantle, and an adjoiningfrusto-conical surface which is substantially less steep than thegeneral slope of the mantle.

3. A crusher as defined by claim 1 in which the mantle includes fourexterior frusto-conical surfaces providing various angles of nip, thetwo lower surfaces being opposite the lower portion of the grinding ringof bulbous character and arranged to provide for an abnormally long wearon the mantle.

4. A crusher as defined by claim 1 in which the thickness of the top ofthe grinding ring is approximately one-third greater than that of thethickness of the bottom of the ring.

5. A crusher as defined by claim 1 in which the reversible grinding ringhas a lower frustoconical grinding surface, a central cylindricalgrinding surface and an upper funnel-shaped grinding surface the angleof slope of which to the axis of the cylindrical surface of the ring issubstantially less than the angle of slope of the lower frusto-conicalsurface thereto.

6. A crusher as defined by claim 1 in which the lower portion of thegrinding ring has a frusto-conical grinding surface and in which themantle opposite said surface includes two adjoining frusto-conica1surfaces of different slope, the upper one of which has an angle ofapproximately 16 with respect to said surface of said ring and the lowerof which is approximately at an angle of 2 with respect to said surfaceof said ring.

7. In a crusher of the gyratory type in which a mantle of generallyfrusto-conical form is mounted within a surrounding grinding ring, theimprovement which comprises a metal end for end reversible grinding ringhaving a lower frusto-conical grinding surface and an upperfunnel-shaped grinding surface, the thickness of the metal at the upperportion of the ring being substantially greater than that at the lowerportion of the ring, whereby when the ring is reversed said extrathickness will compensate for the reduced diameter of the lower portionof the mantle resulting from wear.

8. A crusher as defined by claim 7 in which the angle of slope of saidfrusto-conical surface with respect to the axis of said grinding ring issubstantially greater than the angle of slope of said funnel-shapedsurface with respect to said axis.

9. A crusher as defined by claim 8 in which the thickness of the metalat the top of the grinding ring is approximately one-third greater thanthe thickness of the metal at the original bottom of the ring.

J OSEfPl-I E. KENNEDY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,549,641 Weston Aug. 11, 19251,587,085 Rogers June 1, 1926 1,837,102 Bernhard Dec. 15, 1931 1,957,228Rumpel May 1, 1934 1,985,098 Kennedy Dec. 18, 1934 2,147,833 FahrenwaldFeb. 21, 1939 2,168,582 Rider Aug. 8, 1939 FOREIGN PATENTS NumberCountry Date 683,852 France Mar. 10, 1930 471,842 Great Britain Sept.13, 1937 Patent No. 2,467,938.

Certificate of Correction THOMAS F. MURPHY, Assistant Oomnz'esiomr ofPatents.

